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Bryan, Home Appliance Technician
Category: Appliance
Satisfied Customers: 12156
Experience:  15 yrs. experience as a certified appliance technician.
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Frigidaire Professional upright freezer PLFH1779G53 Recently,

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Frigidaire Professional upright freezer PLFH1779G53

Recently, my freezer, despite being set now on the coldest temp setting, is not freezing well. It seems to running continuously, yet the temp is only about 30 degrees. There is some significant frost on the back of the lower wall, just below the lower lights and behind the bottom drawers.

If you did not include a model # XXXXX your question please do on you second reply if possible,this helps us serve you faster.


the reason it runs all the time is because its not reaching the correct temp.

this is a defrost problem, this happens a lot in Frigidaire freezers, first thing you need to do is remove the back panel in the in inside the freezer and take a hair dryer and defrost all the coils real good, then put the panel back on, then order this, Part(NNN) NNN-NNNN width=its the defrost thermostat, these go all the time, you can order this at and it is snapped to the top of the coils you defrost, inside the freezer, hope this helps , thanks Bryan

Customer: replied 7 years ago.
Dear Bryan,

I have a multimeter. Is there a way to test the part above to insure it's no longer working? I've defrosted the coils (they were covered with ice, so what you describe made sense). Since I've got the cover off, rather than just assume it is this part, how would I (if it's possible) test the system before I put it all back?

Many thanks!

ok, that great you can test this, let the freezer start to cool with the back panel off, shut the door and wait about 1/2 hour then shut the refrigerator off and unplug the thermostat, test it for continuity, the thermostat has to be cold to test this so leave it on the coils, if it has continuity when its colds its good , the next thing to check is the heater, Part 890572unplug this and test it for continuity, this runs under the coils, this should have continuity all the time, if both those parts check out change the timer, Part 890598, these are the only three parts of the defrost system, hope this helps. you can click this blue link for all the diagrams and parts,!retrieveModelDetails.pd?modelNumber=PLFH1779GS3&productCategoryId=0142000&brandId=1428&brandDescription=FRIGIDAIRE&modelName=FREEZER&searchedModel=PLFH1779G53 thanks Bryan

Customer: replied 7 years ago.
Almost done. I'll be out for a bit today before I reply again and pay, but one last question (I think). The thermostat showed continuity after being chilled, and the heating element showed continuity as well. Is there any chance that if someone left the door open for a few hours (cracked open), but was unwilling to admit it (the wife....), could the coils have frozen up and caused the problem on it's own, and that the timer is fine? It has been warm and humid here the past couple of days. In other words, does the problem mean that one of three components MUST be defective?

I'm going to have a chance to leave it for about 6 hours, and if it seems fine, should I change out the timer anyway? Thanks again,


well thats definitely a possibility, you can put it back together and let it run and see, if its going to freeze back up this will happen in about 2-3 weeks,. if by then its still fine then leave it, if it freezes up again change the timer, make sure you put the back panel in the freezer back in, it wont cool correctly if you don't, thanks Bryan
Customer: replied 7 years ago.
Well Bryan, it looks like the freezer is working, with a temp of -1 F. The ice cream is slowly refreezing. So, it looks like this has worked out for the time being. Thank you!

I'll hit the accept answer after this last exchange, just needing to ask you one last question if I may. If if freezes back up again, where is the timer and how do I test and change it?

Many thanks!


in the back of the freezer near the compressor is where the defrost timer is, # XXXXX on this diagram, thanks and well wishes, Bryan
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